Knockdown chair structure



Nov. 24, 1942. McMAl-IAN 2,302,969

xuocxnown CHAIR STRUCTURE Filed Oct. 2, 1940 2 Sheets-Sheet 1 12. INVENTOR ROY F. MCMAHAN ATTORNEY Patented Nov. 24, 194 2 UNHTED S1 i rtii'ltihi'i FEFIQE 7 Claims.

This invention relates to improvements in the construction of chairs, particularly a knockdown chair that may be shipped disassembled in a flat compact carton and readily assembled with simple tools.

One object of the invention is to reduce to a minimum the number of disassembled parts forming the knockdown chair, and the number of securing bolts employed in securing the afore said parts together.

Another object of the invention is to provide a detachable seat member that may be assembled without the aid of tools.

A further object of the invention is to provide interengaging tongues and slots in the rungs and upright frame members at points where the aforesaid members are secured together for reinforcing the connection therebetween.

The advantages of these and other objects will become apparent as the following description is read in connection with the accompanying drawings in which:

Figure l is a plan view of the assembled chair;

Figure 2 is a front elevational view of the assembled chair;

Figure 3 is a sectional View taken along lines 3-3 of Figure 2;

Figure 4 is a. partial sectional view taken along lines 4-4 of Figure 1 for illustrating the construction of the seat member;

Figure 5 is a plan view of the chair with the detachable seat member removed;

Figure 6 is a front elevational view of the chair with the detachable seat member removed;

Figure 7 is a side elevational View of the chair with the detachable seat member removed;

Figure 8 is an enlarged view illustratin the construction of the interengaging connection between the rung 4 and upright frame member 5; and

Figure 9 is a partial sectional view taken along lines 9-43 of Figure 8.

The invention is primarily designed to provide a strong and durable chair for children, and particularly an all-metal chair that may be shipped knockdown and assembled with simple and ordinary tools.

It is well known that the making of chairs has developed into a highly competitive industry. Accordingly, the production of an economical, strong and durable chair has presented many problems. In addition to economy and strength, a metal chair, in order to be commercially satisfactory, must possess an attractive appearance and be relatively free of end edges that may snag or tear clothing.

Therefore, the present invention concerns the production of certain novel constructional features, whereby the various parts of the chair may be made of relatively light-weight material, and shipped knockdown in a small flat shipping carton so as to reduce transportation costs to a minimum. Further, the invention concerns the production of certain novel constructional features that reduce manufacturing costs to a minimum and likewise the number of bolts required to assemble the knockdown parts of the chair.

Thus, with reference to the accompanying drawings, it will be observed that the foregoing requirements have been adequately satisfied by the production of several novel features of construction, which features have collectively contributed to the production of an economical and durable chair.

With particular reference to Figures 5, 6' and 7 it will be observed that the chair comprises two factory-assembled vertical side frames joined by rungs 3, i and 5, and a back rest 3. Each side frame is constructed of light-weight channel material, and comprises an upright member 7 and an arm providing member 6 having a downwardly extending portion terminating in a laterally extending arched-portion forming a rocker. At points 6a and 617, each arm providing member 6 is fixedly secured to its corresponding upright member 1, as, for instance, by spot Welding.

Thus, the chair in knockdown condition comprises, two side frame assemblies composed of parts 5 and l, a back rest three cross rungs l and 5, a seat member 2 and eight assembly bolts la, 3a, 4a, and 5a.

In this respect it is to be observed that each side frame member is suitably apertured for receiving the assembly bolts lo, 311, to and do, likewise the back rest I and the rung i and 5. This construction is particularly illustrated in Figures 7, 8 and 9.

With further reference to Figures 8 and 9, it will be observed that each side frame is slotted adjacent the apertures for the rung bolts 4a. and 5a, and that the free end of each rung 3, 4 and 5 is provided with a tongue A?) that engages its corresponding slot. It is also important to observe that the rungs are likewise formed from light-weight channel material, and that the channel legs 40 are cut away adjacent each end of the rung so that the inner face of the channel base engages the outer face of the base of the channel forming the wide frame. In this respect it is further important to observe that the ends of the channel legs 40 forcibly engage the corresponding side faces of the frame members, and that each tongue 4b fits snugly in its corresponding slot. Accordingly, it will be apparent that this construction and arrangement of the tongues 4b and legs 40 prevents movement of the rungs with respect to the side frames. Thus, the assembly bolts 3a, la and a primarily serve to secure the rungs and frames in place, while the tongues 4b, and the ends of the channel legs 40, serve to provide a very rigid joint connection that is practically free of any possible angular movement between the rungs and side frames.

Therefore, to assemble the chair, the tongues 41) of the rungs 3, 4 and 5 are forcibly pressed into their corresponding slots, and the bolts 3a, 4a and 5a assembled for securing the respective rungs and side frames in place.

The back rest I is then secured to the upper ends of the upright members l by means of bolts la, and the seat member 2 is snapped in place across the rungs 3 and 4, thus forming the assembled chair illustrated in Figures 1, 2 and 3.

For a more complete description of the seat member 2, reference is made to Figure 4. Thus, it will be observed that the lateral edge of the forward end of the seat member 2 is provided with an inwardly turned end 2b preferably of rounded construction as illustrated. The inwardly turned forward end 2?) thus provides a suitable hook that snugly grips the lateral faces of rung 4 as illustrated in Figures 2, 3 and l. The lateral edge of the rear end is preferably formed with a snap lip or catch 2a as illustrated in Fig ure 4, so that the lateral edge of th rung 3 forcibly engages the lateral face of the snap a for securing the seat member 2 in place.

As illustrated in Figure l, the opposed ends of the hook portion 217 may be closed so as to reinforce the inwardly turned end of the hook and also provide vertical edges for engaging the outer face of the rung 4.

Likewise, the longitudinal edges of the seat may be flanged as illustrated for reinforcement. In this respect it is to be observed that the marginal edges of the back rest I are turned rearwardly as illustrated in Figure 3 so as to provide a relatively rigid member even though constructed from light weight material.

While the invention has been illustrated and described in the form of a rocking chair for children it is to be understood that the invention may be embodied in chairs without rockers.

Therefore, the invention is not to be limited other than by the scope of the appended claims. Having thus described my invention, I claim:

1. A knockdown chair comprising, in combination, a pair of spaced side frames; a pair of detachable cross bars connecting the said side frames and lying in the plane for the seat of the chair; and a detachable sheet-metal seat having one end thereof bent downwardly and inwardly to form a hook extending over and around, and in engagement with, one of the cross bars, and having its opposite end bent downwardly and inwardly to form a spring catch engaging the other of said cross bars, for detachably securing the said seat thereto.

2. A knockdown chair comprising, in combination, a pair of duplicate side frames, each consisting of a front member bent to provide in integral sequence an arm section, a front leg section and a sill, and a rear member having one end fixedly secured to the said sill and extending upwardly beyond the said arm section to provide in integral sequence a rear leg section and a back section, the said rear member having the rear end of the said arm section fixedly secured thereto at a point adjacent the lower end of the said backsection; a sheet-metal back-rest extending laterally between the back sections of the respective frames and detachably secured thereto; a detachable cross bar connecting the rear leg sections of the respective side frames and lying in the plane for the chair seat; a detachable cross bar connecting the front leg sections of the respective side frames and also lying in the aforesaid plane for the chair seat; a detachable sheetmetal seat having one end bent downwardly and inwardly to form a hook engaging the cross bar connecting the front leg sections of the side frames, and its opposite end bent downwardly and inwardly to form a spring catch engaging the cross bar connecting the rear leg sections of the side frames, for detachably securing the seat thereto; and interengaging tongues and slots formed in the legs and cross bars at their points of connection, for reinforcing the connections of the bars with the leg sections and preventing movement therebetween.

3. A knockdown chair comprising. in combination, a pair of duplicate side frames of metal, each consisting of a front member bent to provide in integral sequence an arm section, a front leg section and a sill, and a rear member having one end fixedly secured to the said sill and extending upwardly beyond the said arm section to provide in integral sequence a rear leg section and a back section, the said rear member having the rear end of the said arm section fixedly secured thereto at a point adjacent the lower end of the said back section; a sheet-metal backrest extending laterally between the back sections of the respective frames and detachably secured thereto; a detachable cross-bar connecting the rear-leg sections of the respective side frames and lying in the plan for the chair seat; a de tachable cross-bar connecting the front-leg sections of the respective side frames and also lying in the aforesaid plane for the seat of the chair; and a sheet-metal seat having its forward end bent downwardly and inwardly to form a hook extending over and around, and in engagement with the cross-bar connecting the front-leg sections of the said frames, and having its opposite end bent downwardly and inwardly to form a spring catch engaging the cross-bar connecting the rear-leg sections of the said frames, for detachably securing the seat to the said bars.

4. A knockdown chair comprising, in combination, a pair of similar side frames, each. consisting of a front member bent to provide in integral sequence an arm section, a front leg section and a sill, and a rear member having one end fixedly secured to the said sill and extending upwardly beyond the said arm section to provide in integral sequence a rear-leg section and a back section. the said rear member having the rear end of the said arm section. fixedly secured thereto at a point adjacent the lower end of the said back-- section; a sheet-metal back-rest extending laterally between the back sections of the respective frames and detachably secured thereto; a detachable cross-bar connecting the rear-leg sections of the respective side frames and lying in the plane for the chair seat; a detachable crossbar connecting the front-leg sections of the respective side frames and also lying in the aforesaid plane for th chair seat; each leg section having a vertical slot therein adjacent the point of connection of the respective cross-bar, and each cross-bar having its free ends bent rearwardly and each end lodged in the corresponding one or said slots, for reinforcing the respective connections of the bars with the leg sections, and preventing movement therebetween; and a detachable sheet-metal seat having its forward end bent downwardly and inwardly to form a hook engaging the cross-bar connecting the front-leg sections of the side frames, and having its opposite end bent downwardly and inwardly to form a spring catch engaging the cross-bar connecting the rear-leg sections of the side frames, for de" tachably securing the seat thereto.

5. In a knockdown chair comprising, in combination, a pair of spaced side frames; and detachable cross-bars connecting the said frames; each frame member having a vertical slot therein adjacent the point of connection of the respective cross-bar, and each cross-bar having its free 7 ends bent laterally and each end lodged in the corresponding one of said slots for reinforcing the respective connections of the bars with the frames and preventing movement therebetween.

6. A knockdown chair comprising in combination, a pair of opposed side frames, each having a back section and front and rear leg sections rigidly joined together; a back-rest extending laterally between the back sections of the respective frames and detachably secured thereto; a detachable cross-bar connecting the rear-leg sections of the respective frames and lying in the plane for the seat of the chair; a detachable crossbar connecting the front-leg sections of the respective frames and also lying in the aforesaid plane for the chair seat; and a detachable sheetmetal seat having its forward end bent downwardly and inwardly to form a hook extending over and around, and in engagement with, the bar connecting the respective front leg sections of the frames, and having its opposite end bent downwardly and inwardly to form a spring catch engaging the cross-bar connecting the rear leg sections of the frames, for detachably securing the seat thereto.

7. A knockdown chair comprising, in combination, a pair of opposed side frames each having a back section and front and rear leg sections rigidly joined together; a back-rest extending laterally between the back sections of the respective frames and detachably secured thereto; a detachable cross-bar of channel-shaped cross-section connecting the rear-leg sections of the respective frames and lying in the plane for the seat of the chair, the said cross-bar having the legs of its channel extending rearwardly and outwardly relative to the said frames; a second detachable cross-bar connecting the front-leg sections of the respective frames and also lying in the aforesaid plane for the seat of the chair; and a detachable sheetmetal seat having its forward end bent downwardly and inwardly to form a hook extending over and around, and in engagement with, the said second bar, and having its opposite end bent downwardly and inwardly to form a spring catch extending over and engaging the upper leg of the channel-shaped -bar connecting the rear-leg sections of the said frames, for detachably securing the seat thereto.

ROY F. McMAI-IAN. 

